diff -r 7942f613ea5c Lib/urllib/request.py
--- a/Lib/urllib/request.py	Mon Mar 14 09:58:59 2011 -0400
+++ b/Lib/urllib/request.py	Mon Mar 14 11:41:42 2011 -0400
@@ -2257,10 +2257,9 @@
                 mask = m.group(2)
                 if mask is None:
                     mask = 8 * (m.group(1).count('.') + 1)
-
                 else:
                     mask = int(mask[1:])
-                    mask = 32 - mask
+                mask = 32 - mask
 
                 if (hostIP >> mask) == (base >> mask):
                     return True